While at a supported-living facility, the defendant became disgruntled with employees and other residents.
When it became clear Walker would not be relocated, as he wished, he went on a rampage, smashing everything in his way.
He punched and kicked holes in every wall of his unit, court documents said, ripped doors off cupboards and destroyed a fridge, throwing it into a shared courtyard area.
The teen smashed two ranch slider windows and soaked the carpet with water, the court heard.
He was charged with wilful damage.
Walker's actions were a breach of his sentence, and he was evicted from the residence.
When he was required to submit a urine sample for drug analysis the following day, he declined — another breach.
Walker had exhausted his accommodation options and when he appeared in court on June 30 bail was immediately raised by the judge as a problem.
After being stood down in the court cells, the teenager became agitated and started ripping at his clothing, verbally abusing those who monitored him.
When he was brought back before a judge that afternoon his temper boiled over.
Walker was denied bail and as the Corrections officer stepped forward to usher him back to the cells, he turned and punched him twice in the face.
Other staff swarmed in to restrain the defendant while the victim was tended to.
"As a result of the punches the victim sustained a major concussion where he was later admitted to the Dunedin Hospital due to lack of balance and unable to speak properly," police said.
Judge Large heard from youth workers in court to support Walker, who spoke about the measures they would put in place to assist him.
He would be placed in emergency housing initially before a more stable home was found.
Support staff would spend time helping him live independently and others would supervise him looking for voluntary or part-time work.
The judge said Walker had a sad background and an array of issues to contend with, "but you're getting to the age now you have to learn how to manage those conditions, because sadly they're not going to go away".
There was no way the defendant could pay for the damage he caused, Judge Large ruled.
